Change in cutaneous perfusion following 10 weeks of aerobic training in Type 2 diabetes.

A small, but positive, association between aerobic training status or prior maximal exercise and enhanced dorsal foot skin perfusion in active individuals with Type 2 diabetes has been shown. This study, therefore, was designed to examine whether an aerobic training intervention would positively affect cutaneous perfusion in sedentary Type 2 diabetic individuals as well. Nine sedentary participants with Type 2 diabetes (DS) and 10 obese nondiabetic controls (CS) were studied. Prior to the initiation of aerobic training, dorsal foot cutaneous perfusion was measured noninvasively by continuous laser Doppler assessment at baseline and during localized heating to 44 degrees C. These measurements were repeated 48-72 h following 10 weeks of moderate aerobic training performed 3 days per week. Interstitial nitric oxide (NO) levels were measured concurrently in the contralateral foot dorsum. Aerobic training did not significantly enhance baseline skin perfusion, nor were interstitial NO levels different under any condition. At baseline, groups differed only in glycated hemoglobin (HbA1c), fasting serum glucose, HDL-cholesterol, and insulin resistance. At rest, cutaneous perfusion during local heating to 44 degrees C was significantly lower in DS before training, but did not differ significantly from CS afterward. Neither group, however, experienced significant increases in dorsal foot perfusion during local responsiveness to heating to 44 degrees C following 10 weeks of moderate aerobic training, despite slightly lower perfusion in DS before training; these findings were independent of interstitial NO levels. Thus, moderate aerobic training for only 10 weeks does not appear to reverse the impairment in cutaneous perfusion of the foot dorsum in response local heating in a Type 2 diabetic population.

The effect of an aerobic exercise training program on quality of life in type 2 diabetes.

PURPOSE: The purpose of this study was to determine the effect of 10 weeks of moderate aerobic exercise training on quality of life (QOL) and selected physiological parameters in previously sedentary persons with diabetes. METHODS: A quality-of-life survey (SF36v2 health survey) and measurement of physiological parameters were completed before and after 10 weeks of supervised aerobic exercise training 3 days a week for 20 to 45 minutes by subjects with diabetes (n = 9) and control subjects (n = 10). Nontraining subjects with diabetes (n = 12) and control subjects (n = 10) also completed the QOL survey at equivalent times. RESULTS: Participants in all groups had similar characteristics. A training effect was evident in exercisers, with an increase in lactate threshold and a decrease in percent body fat for both groups. Training did not affect body mass index or interstitial nitric oxide levels. Physical and mental component scores on the QOL survey in the training and nontraining groups did not differ significantly before or after the training, and diabetes status had no significant effect on these scores. CONCLUSIONS: No physiological changes were significantly associated with scores on the SF36v2 health survey. In addition, neither training nor the presence of type 2 diabetes significantly affected the physical or mental component scores on the QOL survey.

Cutaneous blood flow in type 2 diabetic individuals after an acute bout of maximal exercise.

OBJECTIVE: We previously demonstrated a positive association between chronic aerobic exercise and dorsal foot skin blood flow during local heating in type 2 diabetic individuals. Thus, we hypothesized that a prior acute bout of maximal exercise would also have positive effects on postexercise blood flow. RESEARCH DESIGN AND METHODS: Subjects consisted of 32 individuals with type 2 diabetes and 26 nondiabetic control subjects further subdivided based on their physical activity status: diabetic exerciser (DE), diabetic sedentary (DS), control exerciser (CE), or control sedentary. Dorsal foot cutaneous blood flow was measured noninvasively by continuous laser-Doppler assessment at baseline and during local heating to 44 degrees C before and after a maximal bout of cycle exercise. Interstitial nitric oxide (NO) levels were measured concurrently in the foot dorsum. RESULTS: Increases in blood flow and its responsiveness to local heating to 44 degrees C were significantly lower in both diabetic groups compared with CE before maximal exercise, but perfusion responsiveness remained lower in DS subjects only after exercise (P < 0.05). Baseline skin blood flow was not different among groups preexercise, but it was significantly increased postexercise in DE subjects only. Interstitial NO levels were not significantly different at either time. At baseline, groups differed only in HbA(1c), fasting serum glucose, HDL cholesterol, and insulin resistance (homeostasis model assessment method). CONCLUSIONS: All diabetic individuals exhibit a blunted responsiveness of cutaneous blood flow with local heating to 44 degrees C before maximal exercise compared with active nondiabetic individuals, but after an exercise bout, it remains significantly blunted only in diabetic individuals who are sedentary. These findings occur independently of changes in interstitial NO levels.